Actually, it is an old myth from horse breeding. In the olden days of many moons ago it was beleived that if a brood mare was covered by an unworthy stud she was ruined. That old myth perpetuated allot of "witch hunting" as such and many good mares were shot. Sad but true.

Although anyone who thinks that it is logic in this day and age is just strange!

HAHAHAHA!! LOL that is about the dumbest thing I have heard in all my life, but then again maybe sperm can survive in dormant stage for up to a year, and the next time the bitch is bred it wakes up and wreaks havoc!!

My step father once tried educating me on horse breeding. He said if a stallion bred to a mediocre mare, or a mare of a different breed he would be 'ruined' which is why AI is done on different breed mares!!